Transcript for New Clues in the Florida State Law Professor Murder Case

New clues in the murder of a prominent law professor. Dan Markel was gunned down at his Florida home and police zeroing in on a car spotted near the scene of the crime. ABC's Matt Gutman has the latest. Reporter: This morning, ABC news has learned exclusively that Florida state law professor Dan Markel was shot in the side of the head at relatively close range Friday morning at his home in this tiny Tallahassee neighborhood. It's the latest in a number of tantalizing new clues about a mystifying murder in a sleepy college town. He was the intended target in this situation. Reporter: Police now putting out pictures of this Toyota prius which they say was seen in the area on the day of the crime. A police tip line also netting 50 tips so far, but one potentially big clue, what wasn't there, no sign of forced entry into the house. There's not enough information to suggest this is a contract murder. It certainly could be. The most likely theory. It's somebody he knows. Reporter: Still with no suspects named, police are being careful not to reveal certain evidence. We must make sure that we are keeping the integrity of this case so we can bring it to the prosecution. The sensitive issue -- Reporter: He was a Harvard grad widely published and left behind two sons and an ex-wife, also an FSU law professor who recently appeared on this internet talk show. Dock thes obtained by ABC news show the two finalized their divorce a year ago but still had been in a battle over access to their two young boys. Tallahassee police say they've questioned Adelson but have not named her or anyone else a suspect. We're speaking to everybody who has an affiliation with Mr. Markel. Reporter: Her client is devastated and scared because she doesn't know who did this or why. And at this point, neither do police. For "Good morning America," Matt Gutman, ABC news, Miami. Let's talk to Dan Abrams about this right now so the biggest clue, no sign of forced entry. What does that tell you. That in conjunction with the fact that he was shot in the head has made it clear to the authorities that this was targeted. This was not random. It wasn't a break-in. It wasn't a robbery. That he was the intended victim here. And I think that's the reason that they've gone public with that information. They want to reassure the public there, the neighbors, et cetera, you don't have to worry, there's not a killer out there on the loose. This was someone who was specifically targeted and that's a really important clue. Why they start to focus on everyone who might have known the professor. Look. We tend to always talk about the personal side of it, right? Involved in a divorce, et cetera, but don't forget the professional side too. A lot of these cases you see people with professional animus towards someone. Would was he working with they'll want to know, maybe things said on his blog, who might have had a motive to want him dead doesn't just mean personal. Is this the kind of case that usually gets solved? Yes, yes, because the fact that they believe he was so specifically targeted allows them to immediately go to the people that have a motive to kill him and I think that it'll likely be solved in the relatively near future. Dan Abrams, thanks very much. Now to an around the world

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